* {
    padding: 0;
    margin: 0;
}

body {
    width: 100%;
    height: 100vh;
    /* 使用 flex 使得 loginBox 在中间 */
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: rgb(0, 11, 32);
    color: #ececec;
}

.loginBox {
    width: 500px;
    height: 500px;
    border-radius: 10px;
    background-color: rgba(0, 0, 0, .5);
    box-shadow: 0px 15px 25px 0px rgba(255, 255, 255, .6);
    padding: 40px;
    box-sizing: border-box;
}

h2 {
    text-align: center;
    color: #fff;
    margin-bottom: 30px;
}

.item {
    height: 45px;
    border-bottom: 1px solid #fff;
    margin-bottom: 40px;
    position: relative;
}

.item input {
    width: 100%;
    height: 100%;
    color: #fff;
    /* 输入框输入光标为白色 */
    padding-top: 20px;
    box-sizing: border-box;
}


/* valid 合法状态下  focus 获取焦点时*/

.item input:focus+label,
.item input:valid+label {
    top: 0;
    font-size: 12px;
}

.item label {
    position: absolute;
    left: 0;
    top: 12px;
    transition: all .2s linear;
    /* linear 匀速 */
}


/* 重置输入框和按钮的样式 */

input,
button {
    background: transparent;
    border: none;
    outline: none;
}

.btn {
    padding: 10px 20px;
    margin-top: 30px;
    color: #fff;
    position: relative;
    overflow: hidden;
}

.btn:hover {
    background-color: #fff;
    border-radius: 5px;
    color: #111;
    /* text-transform: uppercase; */
    /* 文字大写 */
    /* letter-spacing: 2px; */
    /* 字母间隔 */
}
.mark{
    position: relative;
    left: 380px;
}
#footer {
    height: 50px;
	line-height: 40px;
    position: fixed;
    bottom: 0;
    width: 100%;
    text-align: center;
    color: #fff;
    font-family: Arial;
    letter-spacing: 1px;
}